1. Technical Field of the Invention
The present invention relates to a GPS (Global Positioning System) antenna cover which contains a GPS antenna unit, and is mounted on an exterior equipment.
2. Description of the Related Art
GPS systems, which have been extensively used as a positioning system, need a GPS antenna for receiving radio waves from satellites in the constellation of GPS satellites. The installation of this GPS antenna must be done, using a horizontal surface as a reference, and when building a car-carried GPS system, the provision of a GPS antenna mounting mechanism is important.
A GPS antenna itself is flat, and small in size, and generally this antenna and a high-frequency circuit board (for effecting processings for the received radio waves, such as noise removal and amplification) are combined together to form a unit (GPS antenna unit), and this unit is contained in a cover (casing) made of a resin, and this product is mounted on an exterior equipment such as a bracket made of metal.
With respect to car-carried GPS antennas, it is expected that the ratio of genuine products (manufactured by car makers) to optional products, available in the after market, will become high. The genuine products, when to be mounted on a car body, require various brackets of different kinds, depending on the kind of cars, but the antenna maker can not know the configuration of the bracket until the specification of the car is decided by the car maker, and therefore the antenna maker can not spend much time in the development of a new product.
A conventional antenna cover comprises a box top cover, and a bottom cover for closing an opened bottom portion of the top cover after a GPS antenna unit is accommodated in the top cover, and the top cover and the bottom cover are fastened together, for example, by screws or an adhesive.
It is not easy to keep a stock of many kinds of car-carried GPS antenna covers, and also it is not easy to rapidly prepare and produce an antenna cover of a specification for use with a new kind of car. In the case where this antenna cover comprises two parts, that is, a top cover and a bottom cover, much time and labor are required for the assembling operation, and in the case where there are many kinds of antenna covers, there is encountered a problem that the number of the component parts to be stored is large. These are the problems to be solved by the invention.